The Session Initiation Protocol is a signaling communications protocol used in voice and video call over IP networks. Messages formatted according the SIP specification are exchanged between two endpoints such as IP telephones. SIP messages may also be exchanged with a translation server that allows communication between an IP network and a switched telephone network. SIP messages are included in a flow of messages that carry data that describe the message and include data for initiation and maintaining the voice or video call.
Systems exist that process SIP messages as part of a process to deliver SIP messages to an endpoint device. Such processing may be carried out by a session border controller (SBC) or other similar device that carries out PBX functionality for a group of IP enabled communication devices. Many currently available SBC modify SIP messages before they are delivered to their destinations but do not offer configuration abilities where an end-user can change the SBC's behavior. What is needed is a method for configuring SBC and other internet appliances that handle SIP messages such as, for example, a scripting language.